fix: fix hass_url undefined

[danielbrunt57]

Removed self.config.pop("hass_url")
Fixes #2408

[chrisvblemos]

I'm not sure yet why this pop was there to begin with and can't comment on whether removing it could break other things. I think the root issue is at line 815. Solution is very simple, as given by @LorenzoRogai, and should be included anyway even if the .pop is unnecessary as it is a critical error (hass_url doesn't exist in the given context):

Change
CONF_HASS_URL, default=self.config.get(CONF_HASS_URL, hass_url)
to:
CONF_HASS_URL, default=self.config.get(CONF_HASS_URL, DEFAULT_HASS_URL)

[danielbrunt57]

I've compared v4.12.5 with v4.10.3 and in 4.10.3, hass_url was never in _update_schema_defaults:

                vol.Required(
                    CONF_HASS_URL, default=self.config.get(CONF_HASS_URL, hass_url)
                ): str,

I think I added it with the intention it be a reconfigurable option but after a little discussion with Alan, decided to not make it reconfigurable and that section of code lingered. I've tested my config_flow leaving lines 620-621 with config.pop in _test_login as they were previously but removed lines 814-816 in _update_schema_defaults. Initial configuration worked and also a reconfigure options so I believe at this point, that is the correct fix.

[grantclem]

Sadly not working for .com.au